Catheter-related bloodstream infections(CR-BSIs) should be suspected in any febrile patient with a central catheter.
S. aureus, S. epidermidis (coagulase-negative staphylococci), aerobic gram-negative species, and Candida species are most commonly associated with CR-BSIs.
Clinical findings that increase the suspicion of CR-BSIs are local inflammation or phlebitis at the CVC insertion site, sepsis, endophthalmitis, lack of another source of bacteremia, and resolution of fever after catheter removal.
CVC removal is preferred but may involve complex decision making with consideration of host status, need for any type of vascular access, and the identified pathogen.
Remove CVCs in the following settings:
Insertion-site or tunnel-site infection (i.e., pus or significant inflammation at the site).
Candida. S. aureus, and most gram-negative CR-BSIs.
Immunocompromised patients who have fever, neutropenia, and hemodynamic instability.
Nontunneled CVCs should generally be removed for CR-BSI caused by organisms other than coagulase-negative staphylococci.
Most common life-threatening complication in patients receiving CPN (central parenteral nutrition).
S. epidermidis, S. aureus
In immunocompromised:
AIDS, immunosuppressives, chemo, absolute neutrophil count <200, long-term >2 weeks of CPN consider:
Pseudomonas, Enterococcus, Enterobacter, E. coli, Klebsiella, Proteus, Acinetobacter, Candidia, Xanthomonas (PEEEK PACX).
Use the ABX lock technique to treat and prevent CR-BSI. Inj. ABX sol (vanco 2 mg/ml) in the central cath lumen and allow it to sit for 12 hours.
Prevention:
Subclavian CVCS are associated with less CR-BSIs rates than internal jugular CVCs, whereas femoral CVCs have the highest rates of CR-BSIs and should be removed within 72-hours of placement.
Dx: BC before ABx
Tx:
Documentation of clearance of bacteremia after initiation of ABx is critical.
Vancomycin, 1 g IV q12 h is usually appropriate for empiric therapy because the majority of CR-BSIs are staphylococci.
Gram-negative bacilli should be treated broadly, for example, cefepime, 1 g IV q12h, to cover nosocomial pathogens such as Pseudomonas until species identification and susceptibilities are known.
Duration of therapy depends on whether the infection is complicated or uncomplicated. Duration of therapy is counted from the first negative blood culture. Duration should be longer if the CVC remains in situ.
Pathogen-specific therapy:
S. aureus. MSSA, CR-BSIs: oxacillin, 2 g IV q4h, or alternatively with cefazolin, 1 - 2 g IV q8h.
S. aureus. MRSA, CR-BSIs: Vancomycin, 1 g IV q12h. Linezolid, 600 mg PO or IV q12h, or daptomycin, 6 mg/kg IV daily, are alternatives. TEE should be considered if endocarditis is suspected. Duration of therapy is 2 - 4 weeks if TEE is negative, another source is identified, and cultures clear quickly. 4 - 6 wks of treatment is required for suspected endovascular or complicated infections (prolonged bacteremia, suspected catheter-related clot or venous stenosis.
S. epidermidis (coagulase-negative staphylococci) CR-BSI is treated similar to MRSA, with vancomycin being the drug of choice in most cases. Duration of therapy is 5 - 7 days after CVC removal or 10 - 14 days if CVC is retained.
Catheter-related candidemia in hosts who are hemodynamically unstable of have had prolonged fluconazole therapy should be used with caspofungin, 70 mg IV x 1, f/up by 50 mg IV daily while awaiting identification of the species. Patients who are hemodynamically stable and have had low fluconazole exposure, have a Candidia species that is usually sensitive to fluconazole and can be treated with fluconazole, 400 mg IV or PO daily. Duration of therapy should be 14 days after the last positive blood culture result and when signs and symptoms of infection have resolved.